Preheat and Prepare: Preheat your oven to 175°C (350°F). In a bowl, mix the chopped nuts with cinnamon and set them aside.
Layer the Dough: Spread melted butter in a 9x13 baking dish. Layer 10 sheets of the edge dough, buttering each layer generously as you go.
Add the Filling: Sprinkle a layer of the cinnamon-nut mixture over the dough. Follow with 5 more sheets of buttered dough, then add another layer of nuts. Repeat this process until you finish with 10 layers of dough on top.
Cut and Bake: Cut the baklava into diamond shapes and bake for 45-50 minutes until golden brown.
Prepare the Custard: While the baklava is baking, heat the milk in a saucepan. In a separate bowl, whisk together egg yolks, sugar, and flour until smooth. Gradually stir in the warm milk. Return the mixture to the heat, stirring constantly until thickened. Once thick, stir in vanilla and set aside to cool.
Make the Syrup: In another saucepan, bring honey, water, and sugar to a boil, stirring until the sugar dissolves. Let it simmer for about 10 minutes.
Glaze the Baklava: Remove the baklava from the oven and immediately pour the hot syrup over the entire dish.
Cool and Serve: Let the baklava sit for at least 4 hours (best if left overnight) before serving, along with a generous portion of the cooled pastry cream. Enjoy!